The Science of Chocolate

There is something unfathomable about our relationship with chocolate. It’s been around for longer than most civilizations, crossed oceans, can be found all around the world and yet is still only grown in tiny farms in very isolated tropical climates. We use it as a cure-all for broken hearts, rainy days and midnight snacks but there’s more to the way it affects the brain and body than just a sugar rush.

Cocoa (or Theobroma Cacao) translates literally to ‘food of the gods’ and has a chemical quality which is uniquely divine. It contains theobromine, which is toxic to animals like dogs and cats, but works in humans as a stimulant with caffeine.

In addition, cacao contains natural chemicals that work as antidepressants and simulate the feeling of being in love. It also contains flavonoids, which reportedly prevent cancers, protect blood vessels, promote cardiac health, and counteract high blood pressure. So not only does chocolate make your heart happy, it’s actually good for it.

Now this doesn’t mean that you should go out and buy a Cadbury bar a day. Sugar is still a large part of most popular chocolate bars and the positive effects of cacao are most pronounced in high cocoa chocolate bars, so unfortunately the darker and more bitter the chocolate, the more likely it’s doing good things for you. Flavonoids have even been found to be appetite suppressants, so you can literally eat chocolate to help you lose weight.

But this tasty treat takes a little more work to get to your mouth than it takes for you to work it off. Cacao beans may have been around since the ancient Olmecs but it’s still a long journey to turn a cacao bean into the kind of modern chocolate bar that you would recognise in a corner shop.

Cocoa is a very exclusive plant which only grows in tropical climates 20 degrees latitude from the equator. Once planted, cocoa trees take 3-5 years to grow their first crop and each cocoa pod takes 6 months to ripen. Then the beans are harvested from their pods and left in piles to ferment for a week or so. As most plantations are owned by smallholding farmers, they often leave these under banana leaves as they are cheap and easy to source. Then the beans are dried in the sun and graded before being shipped over to Western countries. Despite the fact that cocoa beans have been harvested and grown in South America for thousands of years, many cocoa growers have never even tasted chocolate before.

When the beans arrive in the UK they are roasted to kill bacteria and develop the flavour of the bean, then de-shelled in a wind tunnel in a process called winnowing. After this the cocoa beans are ground down to a fine powder, then the cocoa butter and powder are separately sold, as cocoa butter is often in high demand from cosmetic companies. They are then mixed back together with sugar and milk powder and go through the long, grinding, mixing of the conch.

Conching can take up to 96 hours before the chocolate has achieved that smooth velvety texture. Then the chocolate goes through controlled tempering which breaks down the cocoa crystals and ensures that you get that perfect melt and a good snap. Finally the chocolate is poured into molds, cooled, wrapped in packaging and sent to stores. The whole process takes well over a year of patience and hard work and every stage is one that took centuries of trial and error by different cocoa growers and chocolatiers to get the delicious flavour and smooth texture that is so ubiquitous today.

So when you’re looking for a heart shaped box to buy your loved ones (or yourself) this Valentines, you’re getting something far more than a box of sugary candy. In each decadent bite, you’re sharing in a centuries-old tradition and over a year of hard work to create; an indulgent treat that humanity took centuries to perfect, just because it makes our lives a little sweeter.


The blog this week was by guest writer Claire LeMaster, who has over 7 years of experience in confectionery and chocolate. She works for Smoke and Thyme as our events and marketing manager.

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